Diodes ZLNB1001 User Manual

ZLNB1001
DBS tone and polarity multiplex controller

Description

The ZLNB1001 multiplex controller is one of a wide range of satellite
receiver LNB and IF distribution support circuits available from Zetex.
It supports a single IF path providing logic outputs to select one of four
IF switch input channels, which typically using PIN diodes. It is
intended for use in multi-switch applications for selection and
distribution of universal LNB IF output signals, replacing many discrete
components including the voltage regulator to save both
manufacturing cost and PCB size whilst improving reliability.

The highly accurate control input of the ZLNB1001 has both voltage and tone control for the four
required states. The voltage threshold is nominally 14.5 V and to meet the demanding
requirements of some broadcasters it has a switching range of 14.0 V to 15 V. The threshold is
temperature compensated to minimize drift. This features a low and stable input current that
enables transient protection to be achieved with the addition of only a single resistor.

The outputs are configured to deliver a positive regulated voltage drive of 7 V when a desired
channel is selected, and 0V when de-selected.

Features

■ Precision voltage and tone detectors

■ Temperature compensated

■ Low cost solution

■ Integrated tone filter

■ Powered from STB: no additional power requirement

■ Direct drive to PIN diodes

■ SO8 SMD package

Applications

■ Switch boxes for satellite IF distribution

■ LNB receivers

Pin out - top view

VIN

VPOL

FIN

GND

1

2

3

4

8

VOUT4

7

VOUT3

6

VOUT2

5

VOUT1

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Absolute maximum ratings

Input voltage 25V

Output current 50mA

Operating temperature -40 to 85°C

Storage temperature -50 to 150°C

Electrical characteristics

ZLNB1001

Test conditions (unless otherwise stated): Vin = 10V to 21V via series resistor as test circuit, T

amb

Symbol Parameter Conditions Min. Typ. Max. Units

I

S

I

POL

V

TVPOL

V

TFIN

V

OUTH

V

OUTL

T

SW

Supply current I

Input current at V

*

Threshold voltage T

POL

Tone threshold

Output voltage “high” For selected output,

Output voltage “low” For unselected output,

= 0 1.5 3.2 5.5 mA

OUT

V

= 15V

POL

= 15V

V

in

= -40 to 80°C

amb

V

= 15V

in

f = 22kHz

†

130 220 350 µA

14 14.5 15 V

100 170 350 mV p-p

6.577.5V

I

= 20 mA (source)

OUT

For selected output,

= 0

I

OUT

7.588.5V

0.15 0.5 V

I

= -1 mA (sink)

OUT

Switching speed 10 ms

= 25°C

NOTES:

* Threshold voltage is adjustable using external resistor.
† Waveform of 22 kHz tone is shown in test circuit diagram.

Truth table

Tone V

Off < V

Off > V

On < V

On > V

POL

TPOL

TPOL

TPOL

TPOL

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© Zetex Semiconductors plc 2005

Output 1 Output 2 Output 3 Output 4 Satellite signal

High Low Low Low Low band Vert

Low High Low Low Low band Horiz

Low Low High Low High band Vert

Low Low Low High High band Horiz